1. Field of the Invention
The present invention relates to an image pickup apparatus, a control method, and a program, particularly to an image pickup apparatus, a control method, and a program, which can improve usability.
2. Description of the Related Art
For example, cameras such as a digital (still) camera and a digital video camera generally have a so-called autofocus function.
In the autofocus function, for example, at the center of an image taken by a picture element such as a CCD (Charge Coupled Device) and a CMOS (Complementary Metal Oxide Semiconductor) imager, a focus frame is disposed which is used for focus control, and the focus is controlled in such a way that a high frequency component of the image inside the focus frame is the maximum, that is, the contrast inside the focus frame is the greatest (focus is adjusted).
In the autofocus function before, the focus frame is fixed at the center position of the image taken by the picture element. Therefore, in the cases in which a subject (the image of a subject) to be focused is not inside the focus frame, and the size of a subject inside the focus frame is too small as compared with the size of the focus frame even though it is inside the focus frame, the subject to be focused might not achieve the focus.
Then, for example, the following methods are proposed. The method in which an image taken by a picture element is split into small blocks of a 10 by 10 matrix of pixels, one or more small blocks are specified for a focus frame, and the focus frame in desired size is set at a desired position in a desired shape, and the method in which focus frames are defined in a plurality of patterns, a pattern selection button is operated to select a focus frame used for focus control among the focus frames in the plurality of the patterns, and a scaling button and a cross key (a button for up, down, right and left directions) is operated to further change the position, shape and size of the selected focus frame, as necessary (for example, see JP-A-6-113187).
However, in the method to specify one or more small blocks to be the focus frame and to set the focus frame, it is necessary to specify a small block one by one or multiple blocks by multiple blocks in order to configure a desired focus frame, which hardly has excellent usability. In addition, since the minimum unit of configuring the focus frame is a small block of a 10 by 10 matrix of pixels, the position and size of the focus frame are limited by that small block. For example, it is difficult to set the focus frame at the position at which the border of the focus frame is not matched with the border of the small block. Furthermore, the focus frame can be moved only in a unit of ten pixels which is the matrix size of the small block.
In addition, in the method in which the focus frame used for focus control is selected by operating the pattern selection button, and the position, shape and size of the selected focus frame are changed by manipulating the scaling button and the cross key, as necessary, various manipulations have to be done for setting the focus frame at a desired position, for example, which hardly has excellent usability.